1. Field of the Invention
This invention relates to a repeater in a data communication network using optical signals. This invention also relates to a repeater system providing an optical communication network including a repeater or repeaters.
2. Description of the Prior Art
A known optical radio communication network includes a transmitter, receivers, and repeaters. In the case where a direct optical path between the transmitter and a receiver is blocked, a repeater generally serves to maintain optical radio communication between the transmitter and the receiver. A repeater, which merely amplifies a received optical signal and then outputs a corresponding stronger optical signal, tends to oscillate since a feedback loop is easily formed between receiving and transmitting sections of the repeater. To prevent such an oscillation problem, an optical signal outputted from a transmitter is made into a time-division packet format so that optical signals inputted into and outputted from a repeater can be different from each other in contents. According to time-division packet communication, real-time transmission of information tends to be difficult.